Final Class Yiisoft\Validator\Exception\InvalidCallbackReturnTypeException

                public function __construct(
    /**
     * @var mixed The actual wrong value returned from a callback.
     */
    mixed $returnValue,
    /**
     * @var int The Exception code.
     */
    int $code = 0,
    /**
     * @var Throwable|null The previous throwable used for the exception chaining.
     */
    ?Throwable $previous = null,
) {
    $message = sprintf(
        'Return value of callback must be an instance of "%s", "%s" returned.',
        Result::class,
        get_debug_type($returnValue),
    );
    parent::__construct($message, $code, $previous);
}

            

                public function getName(): string
{
    return 'Invalid callable return value';
}

            

                public function getSolution(): ?string
{
    return <<<SOLUTION
callback must return an instance of `\Yiisoft\Validator\Result`. An example of a valid callback:
hp
Yiisoft\Validator\Result;
ic function (mixed \$value): Result
\$result = new Result();
if (!in_array(\$value, [7, 42], true)) {
    \$result->addError('Value must be 7 or 42.');
}
return \$result;
TION;
}